In the market there are several types of wringing tools for mops having a single, freely rotating roller mounted on the end of a pair of oscillating arms which are fixed on a pivoting shaft supported in the top part of a box structure for a mop bucket open at the top. The pivoting shaft is rotated by a hand lever, while a roller, which is coaxial or substantially coaxial with this shaft and supported by oscillating arms, moves in front of a bent wringing surface corresponding to a part of a surface of a cylinder which is coaxial with the aforesaid pivoting shaft. Between the roller surface and the wringing surface there is a uniform or a substantially uniform opening for the roller which is moved by an oscillation motion of the oscillating arms. Some of the afore described wringing tools, with a roller working against a bent wringing surface, to improve their functioning, are provided with springs inside each of their oscillating arms. These springs exert a thrust force on the movable roller which presses against the wringing surface.
At this point, it must be remembered that the overall dimensions of the box constituting the wringing tool""s framework must be contained both as regards width and as regards length because they cannot be larger than the structures the wringing tools are to applied to. Among the above mentioned wringing tools there is the tool of Japanese model 52.347, the wringing tool of U.S. Pat. No. 4,852,207 to Yamane, and the wringing tool of EP 480 327 to VDM s.r.l.
In order to move the arms directly by the hand lever, only one shaft is used and both the lever and the arms are fixed thereto. Indirect moving is carried out by two shafts. On one shaft the hand lever is fitted while on the other shaft the arms are fixed.
It is one of the fundamental principles of mechanics that for the multiplication and gearing down of the motion between two shafts, (what the shaft transmitting the motion is the operator and the other shaft which receives the motion is the user) the connection is carried out either by pulleys and belts, by the gears or by a rods. The two shafts are usually parallel between them. The shafts taken into consideration are called primary or secondary according to the function that each of the two shafts undertakes in the functionality of its use.
There are several problems associated with wringing tools having movable roller pressing on a bent wringing surface.
One problem is caused by the fact that the oscillation angle of the levers supporting the operator roller is identical to that of the hand lever controlling the movement so that the roller distance against the wringing surface is reduced and is shorter than the length of the fringes strip to be wrung. For this reason, at least two further wringing operations are needed in order to cover the whole extension of the fringes strip to be wrung.
Another problem is caused by the fact that in order to increase the oscillation angle of the levers supporting the operator roller in comparison with the oscillating angle of the hand lever controlling the movement, some driving means interpose and force these supporting roller levers"" length to be shortened. Consequently the curvature of the wringing surface, against which the roller works, increases. Since the size of the top or upper opening of the wringing tool must be kept open enough for the insertion of the mop to be wrung, the increased bending of the wringing surface causes the opening at the bottom to be reduced.
This causes the problem of not having enough free space to allow the mop and its support to pass through the wringing tool""s box structure bottom opening.
In this case, it is necessary to be supplied with a separate rinsing basin in addition to the one below the wringing tool and to make a double movement with the mop and its support. This cause an operator to have to do two different operations therefore demanding increased time.
Rinsing in a basin displaced from the basin below the wringing tool makes it easy to spill fluid with obvious consequences.
A further problem is caused by the driving means which transfer the motion of the shaft moved by the control hand lever to the levers supporting the operator roller, if these driving means are constituted of other levers and rods which are exposed.
Exposed kinematic mechanisms present problems concerning functionality and safety.
A wrong insertion of a mop in the wringing tool can damage the moving parts of the kinematic mechanisms while the accidental insertion of fingers in the kinematic mechanisms can cause serious injury to a person.
There is another problem when the angular movement of the support levers for the operator roller is identical to that of the motion control hand lever. In this case, the angular travel distance without activity going from the rest position where a roller is completely lifted up to its approach to the top edge or border of the wringing bent surface causes needless wear of the wringing tool mechanism.
A further problem comes with the use of a driving means constituted of levers and rods transferring the motion of the shaft moved by the control hand lever to the levers supporting the operator roller. In this case, the angular movement of the control hand lever compared with that of the levers supporting the operator roller, is carried out neither gradually nor according to a logic sequence of demanded efforts because the movement of the different kinematic elements is dependent on the structure. In addition to this, the moving levers stop when the levers are blocked because they interfere against fixed elements. Consequently the extent of the oscillation of the levers supporting the operator roller presents some limits and consequently limits the travel of the operator roller. The wringing tool of the present invention provides a solution for these and other problems.
The wringing tool of the instant invention has a box structure without a cover and with an open bottom, and idle or wringing roller which is supported on the ends of two oscillating levers, and a hand lever which transmits motion to the oscillating levers supporting the wringing roller by means of gears assembled on a shaft driven by the hand lever itself. In order to make the wringing tool stronger, the oscillating levers may be joined together by a frame forming a support which, on its upper end, terminates in a fork shape for the assembly of a shaft which supports the wringing roller. The box structure of the wringing tool also has a front wall which has seats properly shaped for the assembly of the box structure so that the lower opening is above a basin below. The side walls contribute to support the kinematic mechanisms for moving the pressure roller. The wall opposed to the front bearing wall has a curvilinear shape which is engaged when the mops and/or the fringes strips are wrung by the pressure roller.
Inside the box structure there are no driving means consisting of levers and rods connected to the oscillating levers supporting the roller.
According to the invention the oscillating levers supporting the wringing roller are integral with a shaft supported by the side walls. This shaft mounts at least one roller gear placed outside the aforesaid walls. The roller gear is moved by an inner toothed gear fitted on a shaft moved by a control hand lever. Helical springs are fixed with one end on the side walls and the other end on the outside periphery of the inner toothed gear such that the springs bring the kinematic mechanisms from an end position of the wringing operation to a rest position at the beginning phase. The shaft, which the operator roller idles on, is retained in correspondence to seats placed on the ends of the oscillating levers by screws which engage niches made on the outside surface of the levers. This fact establishes the ease and the functionality of the roller assembly and disassembly thereof (and also of its replacement) by removing or inserting the screws engaged on the lever niches.